Wet subtropical storm possible for Florida this weekend

A large low pressure system with heavy rains is expected to develop over Cuba and South Florida on Saturday. The counter-clockwise flow around this low will bring strong winds and heavy rains to much of the Florida coast on Saturday, and these conditions will spread northwards to Georgia by Sunday and South Carolina by Monday. Most of the models develop this system into a tropical or subtropical storm, but the potential location of such a storm is still murky. The ECMWF model predicts the storm will form in the eastern Gulf of Mexico on Monday, then move north into the Florida Panhandle on Tuesday. If this track verifies, the oil rigs off the coast of Southeast Louisiana may experience a one or two day period of sustained winds above tropical storm force Monday or Tuesday. The GFS and NOGAPS models put the storm on the other side of Florida, over the Northwestern Bahamas, and predict the storm will move northwards and hit North Carolina on Wednesday. The UKMET model is in-between, developing the storm right on top of Florida. Since the storm is going to be getting its start as a cold-cored upper-level low pressure system with some dry air aloft, it will probably start out subtropical, with a large band of heavy rain developing well north of the center, bringing heavy rains to a wide region of the Southeast U.S. Subtropical storms cannot intensify quickly, due to their lack of an organized inner core. If the storm follows the path of the GFS model, it could be similar to Subtropical Storm Four of October 4, 1974. That storm brought 10 - 14 inches of rain to the east coast of Florida and strong onshore winds of 30 - 40 mph that caused beach erosion and coastal flooding. The extended forecast discussion from NOAA's Hydrometeorological Prediction Center has a more technical discussion of this coming storm for those interested.

Figure 1. Rainfall forecast for the 5-day period ending at 8 am EDT Monday, October 10, 2011. The storm system affecting Florida this weekend is expected to bring up to 7 inches of rain along the coast. Image credit: NOAA/HPC.

Tropical Storm Philippe no threat to landIn the middle Atlantic, Tropical Storm Philippe is about to interact with a frontal system and turn northeastward out to sea. Satellite loops show Philippe is a small system with a modest amount heavy thunderstorm activity, with the surface circulation partially exposed to view by wind shear. Wind shear will remain in the moderate range today, which may allow the storm to intensify into a hurricane, as predicted by several of the intensity forecast models. By Thursday, wind shear will rise to a very high 30 - 50 knots, which should cause rapid weakening. Philippe will not trouble any land areas.

Figure 2. Morning satellite image of Tropical Storm Philippe. The band of clouds to the northwest of Philippe is associated with a cold front that is expected to absorb the storm and recurve it to the northeast on Thursday.

Odds are that a sub-tropical storm will form next week off Florida from that frontal boundary. The models are shifting back and forth with what scenario to believe, as the 12z GFS and 12z ECMWF now both say that this will move into the Gulf, perhaps strengthening just off the coast of Tampa. This system will more than likely attempt to gain a fully tropical core, but I do not see a hurricane out of this. If you want to see another major hurricane, the Western Caribbean is your best bet. A VERY intense MJO upward phase is going to come through this basin mid-month, we will probably see at least 2-3 systems form in there this month.

Quoting Jaxen:Nuts. I have my golf club championship in Orlando this weekend, I got my mother-in-law to come up from Naples to help with my 3-year-old while I'm out, and I may have just wasted a favor if we get washed out.

Ah, but the joy of having your mother-in-law there will outweigh that! :}

Quoting weaverwxman:Wow rita that is a bold statement can you give us some facts as to your thinking. I see you post alot and seem pretty knoledgeable. Do you have an in with the NWS and no something we don't know?

I'm expecting Tropical/Subtropical storm conditions as early as the weekend into nearly next week. Will be interesting. Again, the season is NOT by any means close to over, we still have 2-5 possible systems left. I think we may get to the Greek Alphabet once again this year.

A 2 week parallel for the latest set of changes is ongoing. The changes fix a failure of the fire weather nest run and a model output problem causing too weak vertical velocity to be displayed. SPC and AWC are encouraged to check the output. Implementation is scheduled for 12 UTC 18 October.

Quoting LargoFl: local weather guys are beginning to prep us for this coming weekend, one suggested with a stalled sub or tropical storm because of that large high to the north we Could..see 7-10 inches of rain, possibly more..now thats alot of rain, street flooding etc for sure..add TS winds and tree's could come down due to the soggy soil...whew gotta clean out the gutters etc lol..

Keep in mind, this isn't the northeast, 7 to 10 inches of rain is nothing we can't handle, I live in a low lying area in Pinellas, we don't really see significant flooding till rainfall hits 8 to 10 inches in one day. Also trees are very strong here, even after hours hours of strong tropical storm strength winds (50 to 70 mph with a brief period of slightly higher) from Frances and Jeanne, as well as a combined 16 inches from both storms, there were still not many fallen trees. We actually saw more power line damage then tree damage, because the old power grid built by Florida power is still in place, which is a pretty weak system. The new power company is better, but we are still feeling the effects. Tampa's is worse than ours though, TECO sometimes does things with their high voltage lines that scares me, like very weak supports, and sometimes massive transmission lines, 100 to 300 kv running at unusually low altitudes right in the city.

Unlike the East Coast of Florida, we have actually had above normal rainfall in many spots along Florida's West Coast, so the ground is still quite wet. There will probably be some isolated wind damage and some street flooding if a nice low spins up on the gulf side.

*UPDATE-1:* THE AMSR-E INSTRUMENT ABOARD THE AQUA SPACECRAFT REMAINSOFF-LINE. NASA WILL BE CONDUCTING A MEETING NEXT TUESDAY (OCTOBER11) TODECIDE ON THE FUTURE OF THE INSTRUMENT. THE INSTRUMENT WILL REMAIN INSAFEMODE AT LEAST THEN. NO DATA WILL BE PROCESSED.

*DATE/TIME ISSUED: *OCTOBER 05, 2011 1600 UTC**

*PRODUCT(S) OR DATA IMPACTED:*AQUA AMSRE

*DATE/TIME OF INITIAL IMPACT:*OCTOBER 04, 2011 0658 UTC**

*DATE/TIME OF EXPECTED END: *UNKNOWN**

*LENGTH OF EVENT:* TBD**

*DETAILS/SPECIFICS OF CHANGE:*AT APPROXIMATELY 0658 UTC THIS MORNING,THE AMSR-E INSTRUMENT ON THE AQUA SPACECRAFT SPUN DOWN AND STOPPEDTAKING OBSERVATIONS. THE SITUATION IS BEING INVESTIGATED. THERE IS NOTIMELINE FOR RESTORATION OF SERVICE.*UPDATE-1:* THE AMSR-E INSTRUMENT ABOARD THE AQUA SPACECRAFT REMAINSOFF-LINE. NASA WILL BE CONDUCTING A MEETING NEXT TUESDAY (OCTOBER11) TODECIDE ON THE FUTURE OF THE INSTRUMENT. THE INSTRUMENT WILL REMAIN INSAFEMODE AT LEAST THEN. NO DATA WILL BE PROCESSED.

:( Not sure but hopefully this is not the start or a larger issue.

On another note... do you have info on when NAM Para would replace the current version? I though Sept. 20th, but appears that wasn't the case.

Odds are that a sub-tropical storm will form next week off Florida from that frontal boundary. The models are shifting back and forth with what scenario to believe, as the 12z GFS and 12z ECMWF now both say that this will move into the Gulf, perhaps strengthening just off the coast of Tampa. This system will more than likely attempt to gain a fully tropical core, but I do not see a hurricane out of this. If you want to see another major hurricane, the Western Caribbean is your best bet. A VERY intense MJO upward phase is going to come through this basin mid-month, we will probably see at least 2-3 systems form in there this month.

this is what the local weather guy was mentioning, could be right out near tampa bay, stalled...something to watch and prepare for alright

Quoting LargoFl: local weather guys are beginning to prep us for this coming weekend, one suggested with a stalled sub or tropical storm because of that large high to the north we Could..see 7-10 inches of rain, possibly more..now thats alot of rain, street flooding etc for sure..add TS winds and tree's could come down due to the soggy soil...whew gotta clean out the gutters etc lol..

SHOWERS AND THUNDERSTORMS ARE GRADUALLY BECOMING BETTER ORGANIZED IN ASSOCIATION WITH AN AREA OF LOW PRESSURE LOCATED ABOUT 825 MILESSOUTHWEST OF MANZANILLO MEXICO. CONDITIONS APPEAR FAVORABLE FORADDITIONAL DEVELOPMENT...AND THIS LOW IS LIKELY TO BECOME A TROPICALDEPRESSION DURING THE NEXT DAY OR TWO AS IT MOVES WEST-NORTHWESTWARDAT ABOUT 10 MPH. THIS SYSTEM HAS A HIGH CHANCE...70 PERCENT...OFBECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS.

SHOWER AND THUNDERSTORM ACTIVITY ASSOCIATED WITH A LOW PRESSURE AREA CENTERED ABOUT 525 MILES SOUTH-SOUTHWEST OF ACAPULCO MEXICO HAS BECOME A LITTLE BETTER ORGANIZED THIS MORNING. ENVIRONMENTALCONDITIONS APPEAR CONDUCIVE FOR DEVELOPMENT...AND THIS DISTURBANCECOULD BECOME A TROPICAL DEPRESSION DURING THE NEXT DAY OR TWO. THIS SYSTEM HAS A MEDIUM CHANCE...50 PERCENT...OF BECOMING ATROPICAL CYCLONE DURING THE NEXT 48 HOURS AS IT MOVES TOWARD THEWEST-NORTHWEST AT ABOUT 10 MPH.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THENEXT 48 HOURS.

.LONG TERM...SATURDAY THROUGH SUNDAY...TOUGHEST PART OF THISFORECAST PACKAGE. LONG RANGE MODELS SHOW A WEAK UPPER LOWDEVELOPING JUST SW OF THE LOCAL AREA BY FRIDAY NIGHT AND MOVINGSLOWLY WESTWARD. ACCORDING TO GFS AND TO SOME DEGREE, THE ECMWF,THIS LOW SHOULD INTERACT WITH THE STRONG LOW LVL MOIST ATLANTICFLOW TO FURTHER ENHANCE THE SHOWER ACTIVITY. GFS NOW HAS A SFC LOWDEVELOPING ALONG THE FRONTAL BOUNDARY MENTIONED BEFORE, BUTFURTHER WESTWARD. IN FACT MOVES IT NORTHWARD OVER THE FLORIDAPENINSULA. 00Z ECMWF STILL POINTS TO A DEVELOPMENT OVER THE ERNGULF OF MEXICO. THIS, OF COURSE, PRODUCES TWO DIFFERENT SCENARIOS.GFS NOW SHOWS THE HEAVIEST PRECIP OVER CENTRAL FLORIDA SATURDAYTHROUGH SUNDAY AS A CONVERGENCE BANDS DEVELOPS NORTH OF THEDEVELOPING LOW. ECMWF, ON THE OTHER HAND, HAS A BAND DEVELOPINGACROSS THE LOCAL AREA AS THE LOW BEGINS TO DEVELOP JUST NW CUBASATURDAY THROUGH SUNDAY. DECIDED TO INCREASE THE CHANCE FOR RAINALL AREAS SATURDAY TO ACCOUNT FOR THE INCREASED EAST FLOW AND THEPOSSIBILITY OF THE SFC LOW BEING JUST SOUTH OR SOUTHWEST OF SOUTHFLORIDA...HOWEVER UNCERTAINTIES ON WX CONDITIONS FOR SUNDAY STILLPRETTY HIGH. THERE IS A POTENTIAL FOR HEAVY RAIN THROUGH THISPERIOD...ESPECIALLY ACROSS EASTERN AREAS OF SOUTH FLORIDA.

THE STRONG EAST FLOW WILL ALSO RESULT IN AN INCREASED RISK OF RIPCURRENTS AND POSSIBLY BEACH EROSION ALONG THE ATLANTIC BEACHESTHROUGH THE WEEKEND.

local weather guys are beginning to prep us for this coming weekend, one suggested with a stalled sub or tropical storm because of that large high to the north we Could..see 7-10 inches of rain, possibly more..now thats alot of rain, street flooding etc for sure..add TS winds and tree's could come down due to the soggy soil...whew gotta clean out the gutters etc lol..

Odds are that a sub-tropical storm will form next week off Florida from that frontal boundary. The models are shifting back and forth with what scenario to believe, as the 12z GFS and 12z ECMWF now both say that this will move into the Gulf, perhaps strengthening just off the coast of Tampa. This system will more than likely attempt to gain a fully tropical core, but I do not see a hurricane out of this. If you want to see another major hurricane, the Western Caribbean is your best bet. A VERY intense MJO upward phase is going to come through this basin mid-month, we will probably see at least 2-3 systems form in there this month.

*UPDATE-1:* THE AMSR-E INSTRUMENT ABOARD THE AQUA SPACECRAFT REMAINSOFF-LINE. NASA WILL BE CONDUCTING A MEETING NEXT TUESDAY (OCTOBER11) TODECIDE ON THE FUTURE OF THE INSTRUMENT. THE INSTRUMENT WILL REMAIN INSAFEMODE AT LEAST THEN. NO DATA WILL BE PROCESSED.

*DATE/TIME ISSUED: *OCTOBER 05, 2011 1600 UTC**

*PRODUCT(S) OR DATA IMPACTED:*AQUA AMSRE

*DATE/TIME OF INITIAL IMPACT:*OCTOBER 04, 2011 0658 UTC**

*DATE/TIME OF EXPECTED END: *UNKNOWN**

*LENGTH OF EVENT:* TBD**

*DETAILS/SPECIFICS OF CHANGE:*AT APPROXIMATELY 0658 UTC THIS MORNING,THE AMSR-E INSTRUMENT ON THE AQUA SPACECRAFT SPUN DOWN AND STOPPEDTAKING OBSERVATIONS. THE SITUATION IS BEING INVESTIGATED. THERE IS NOTIMELINE FOR RESTORATION OF SERVICE.*UPDATE-1:* THE AMSR-E INSTRUMENT ABOARD THE AQUA SPACECRAFT REMAINSOFF-LINE. NASA WILL BE CONDUCTING A MEETING NEXT TUESDAY (OCTOBER11) TODECIDE ON THE FUTURE OF THE INSTRUMENT. THE INSTRUMENT WILL REMAIN INSAFEMODE AT LEAST THEN. NO DATA WILL BE PROCESSED.

Quoting tropicfreak:Meanwhile, check out that noreaster in the Canadian Maritimes. Very impressive looking.

Yeah its been quite the interesting week... Us in N.S. have gotten all of October's normal rainfall in the last 5 days... and enough wind to snap branches off trees... Beaufort scale = 9

This raises the statement/question again that I have believed for years is that I think Nor'Easters and "terracanes" (like the ones that caused the tornadoes this year) should be named. They do at least and sometimes more damage than tropical storms, and cause a lot of death and panic.

Quoting Jedkins01:I'm not really sure why most people keep talking about the system forming on the East side of Florida so much as if that is the consensus. I mean, there isn't exactly a consensus at all yet, but if there was one, it would be on the West side of Florida. Why? Well, the GFS and NOGAPS are really the only main models showing it forming in the Bahamas and moving up the East Coast. Whereas multiple models are saying it will move right up over Florida or on the West side of Florida.

Furthermore, look to the South, what makes most since to you, low pressure initiation between Cuba and Mexico, the Florida straights, or the Bahamas? The Florida Straights over to between Mexico and Cuba are more likely places for low pressure formation, not only because there is more lift over that part of the stalled front, but also because the tail end of fronts is a classic place for cyclone formation.

I'm not saying it won't form on the east side of Florida, but that seems the least likely of the solutions, which is why I'm not sure why the HPC is going with that thinking. The local NWS offices in Central and South Florida also make note that low pressure on the tail end of fronts is more common rather then it forming further east.

Anyways, we shall see.

I wouldn't call it the least likely solution, because with the trough located over Florida like the models are suggesting, air would be diverging on the eastern side and causing low pressure to form.

I hear ya...crazy how quiet it is in here with possible Florida related tropical mischief. Normally upon hearing models possibly targeting Florida, I run outside and scream with my arms flailing for a good 10 minutes. But I'm not feeling it right now. I'm even repressing the urge to declare that we are all DOOM!

Even worse, there's a chance that Oktoberfest in Lantana could get rained out!!

Letting a little precip stop the beer drinking... Lantana Lou would be sad.

Can someone please help me..I am signed in to WU,as I am a paying member, but when I click on mail, it says I have to be a registered member...It won't let me access it at all. Is anyone else having this problem?

I hear ya...crazy how quiet it is in here with possible Florida related tropical mischief. Normally upon hearing models possibly targeting Florida, I run outside and scream with my arms flailing for a good 10 minutes. But I'm not feeling it right now. I'm even repressing the urge to declare that we are all DOOM!

Even worse, there's a chance that Oktoberfest in Lantana could get rained out!!

Quoting petewxwatcher:It will be better for Florida if a strong low does not develop for a lot of reasons. Not getting strong winds is one. But the other is that if a strong low develops subsidence near the low may cut off rainfall. A big breezy disorganized soaking would be best for all concerned I think!

We could use the rain here in ECFL. Our rainy season has been pretty dry. No one wants another TS Fay for certain! (25+ inches of rain here.) I have to agree with your big breezy disorganized soaking being the best scenario.

Our local NWS WFO has been talking about this system for days. We were going to head over to Sanibel for the long weekend and decided to stay put. My son is a meteorology student and this was his first break at school -- his next break will be during snowbird/tourist season so no Sanibel for us! Maybe next year. ;-)